更新时间:2024-12-06 GMT+08:00
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MOVE

功能描述

MOVE在不检索数据的情况下重新定位一个游标。MOVE的作用类似于FETCH命令,但只是重定位游标而不返回行。

注意事项

无。

语法格式

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MOVE [ direction [ FROM | IN ] ] cursor_name;

其中direction子句为可选参数。

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NEXT
   | PRIOR
   | FIRST
   | LAST
   | ABSOLUTE count
   | RELATIVE count
   | count
   | ALL
   | FORWARD
   | FORWARD count
   | FORWARD ALL
   | BACKWARD
   | BACKWARD count
   | BACKWARD ALL

参数说明

MOVE命令的参数与FETCH的相同,详细请参见FETCH的参数说明

成功完成时,MOVE命令将返回一个“MOVE count”的标签,count是一个使用相同参数的FETCH命令会返回的行数(可能为零)。

示例

开始一个事务:

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START TRANSACTION;

定义一个名为cursor1的游标:

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CURSOR cursor1 FOR SELECT * FROM tpcds.reason;

忽略游标cursor1的前3行:

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MOVE FORWARD 3 FROM cursor1;

抓取游标cursor1的前4行:

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FETCH 4 FROM cursor1;
 r_reason_sk |   r_reason_id    |                                            r_reason_desc                                             
-------------+------------------+------------------------------------------------------------------------------------------------------
           4 | AAAAAAAAEAAAAAAA | Not the product that was ordred                                                                     
           5 | AAAAAAAAFAAAAAAA | Parts missing                                                                                       
           6 | AAAAAAAAGAAAAAAA | Does not work with a product that I have                                                            
           7 | AAAAAAAAHAAAAAAA | Gift exchange                                                                                       
(4 rows)

关闭游标:

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CLOSE cursor1;

结束一个事务:

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END;

相关链接

CLOSEFETCH

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